21126528 has 64 divisors (see below), whose sum is σ = 62362800. Its totient is φ = 7041024.

The previous prime is 21126517. The next prime is 21126533. The reversal of 21126528 is 82562112.

It is a happy number.

21126528 is a `hidden beast` number, since 2 + 1 + 1 + 2 + 652 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 400 + ... + 6512.

Almost surely, 2^21126528 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21126528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31181400).

21126528 is an abundant number, since it is smaller than the sum of its proper divisors (41236272).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21126528 is an equidigital number, since it uses as much as digits as its factorization.

21126528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6136 (or 6118 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 21126528 is about 4596.3602991933. The cubic root of 21126528 is about 276.4454055867.

The spelling of 21126528 in words is "twenty-one million, one hundred twenty-six thousand, five hundred twenty-eight".